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Operation of an X-ray transition-edge sensor cooled by tunnel junction refrigerators



Nathan A. Tomlin, James A. Beall, Gene C. Hilton, Kent D. Irwin, Galen O'Neil, Dan Schmidt, Leila R. Vale, Joel Ullom


We demonstrate successful cooling of an X-ray transition-edge sensor (TES) using solid-state refrigerators based on normal-metal/insulator/superconductor (NIS) tunnel junctions. Above the TES transition temperature (Tc), we use Johnson noise thermometry to measure the cooling performance. In this regime, the NIS refrigerators cool the TES from 300 mK to 220 mK and from 220 mK to Tc = 160 mK. Below Tc, we clearly see cooling and observe that the operation of the NIS refrigerators introduces no detectable noise into the TES readout. However, due to the complicated thermal circuit, we are currently unable to quantify the cooling below Tc without further measurements.
Journal of Low Temperature Physics


NIS junction, Refrigeration, TES, Tunneling, X-ray detector


Tomlin, N. , Beall, J. , Hilton, G. , Irwin, K. , O'Neil, G. , Schmidt, D. , Vale, L. and Ullom, J. (2008), Operation of an X-ray transition-edge sensor cooled by tunnel junction refrigerators, Journal of Low Temperature Physics, [online], (Accessed April 21, 2024)
Created January 18, 2008, Updated October 12, 2021